Very large volcanic eruptions could lead to ice sheet instability

The Antarctic ice sheet. Credit: Stephen Hudson / Wikipedia

Massive volcanic eruptions could cause localised warming that might destabilise some of the world’s biggest ice sheets, according to new research from Durham University.

Scientists investigated links between very and polar temperatures during the last Ice Age.

Their findings suggest that some periods of Antarctic warming between 30,000 to 80,000 years ago were triggered by huge volcanic eruptions in the Northern Hemisphere that caused a shift in the world’s weather patterns.

The Northern Hemisphere cooled as volcanic particles reflected the sun’s heat, forcing warmer weather fronts south which led to warming in Antarctica, the researchers said.

Conversely, their research suggests that Southern Hemisphere eruptions could also have triggered abrupt warming in Greenland during the last Ice Age.

The findings are published in the journal Scientific Reports.

The Durham team said their findings showed that the potential effects of eruptions should be considered when predicting future climate change.

Previous research shows that there were several episodes of rapid and substantial Greenland warming of around 10C during the last Ice Age.

Such a rise could potentially have catastrophic consequences for the Greenland sheet and sea level rise if this were to happen today.

Lead author Dr James Baldini, in Durham University’s Department of Earth Sciences, said: “Although this might not be an immediate threat, we should consider this new perspective regarding the effects that very large volcanic eruptions might have on future climate change.

“Current climatic background conditions are different now than they were during the last Ice Age as there are no large Northern Hemisphere ice sheets to amplify the effects of the original eruption.

“However, man-made greenhouse gas and sulphate emissions since the Industrial Revolution have already had an effect on weather patterns.

“We have to consider the reality that a large volcanic eruption could add to this problem in an unexpected way.

“For example, a large Northern Hemisphere eruption producing even only moderate Antarctic warming, when combined with an already unstable West Antarctic Ice Sheet, could have very serious consequences.”

MORE of the story / click image TOP of PAGE